Arsenic

Metalloid · 74.92159 u · group 15, period 4

Arsenic · As

Atomic number33

SymbolAs

CategoryMetalloid

Standard stateSolid

Group · Period · Block15 · 4 · p

Electron configuration[Ar]4s2 3d10 4p3

Atomic mass74.92159 u

Atomic radius185 pm

Protons / Neutrons / Electrons33 / 42 / 33

Shells (e⁻ per shell)2, 8, 18, 5

Electronegativity (Pauling)2.18

Ionization energy9.815 eV

Electron affinity0.81 eV

Oxidation states+5, +3, -3

Melting point1.09e+3 K · 816.9 °C

Boiling point887 K · 613.9 °C

Density5.776 g/cm³

Year discoveredAncient

CPK color

#BD80E3

State at room temp (25 °C)

solid

Position

1 in library